1. Field of the Invention
The present invention relates to a planar illumination device and a method of manufacturing the planar illumination device.
2. Description of the Related Art
There is a planar illumination device in which a light emitting diode (LED) mounted on a substrate by a solder, such as a top view type LED and a side view type LED, is arranged so as to face a light incident surface of a light guide plate.
Conventionally, a technique of self-alignment for correcting misalignment or inclination (a posture change) of an LED caused by melting of a solder in the case of soldering the LED has been known.
In recent years, a light guide plate has become thinner relative to the thickness of the top view type LED along with a demand for narrowing of a frame of a planar illumination device. Even under such a circumstance, it is necessary to align the LED and the light guide plate with high accuracy in order to obtain sufficient brightness characteristics, and accordingly, it is necessary to mount the LED on the substrate with high accuracy.
In the above-described conventional technique, however, the mounting accuracy of the LED deteriorates due to the action of self-alignment, and accordingly, there is a case where it is difficult to obtain the sufficient brightness characteristics.